Core C will provide expert oversight, training, and support to all statistical analyses in this Program Project. The Core will construct and update databases, verify and clean data, and select and apply statistical analyses attuned to nuances of the data. All three of the research projects will make use of Core C to select appropriate techniques to analyze behavioral data. In addition, the task of developing adequate models of growth, particularly in relation to linguistic input, is one that is relevant to Projects I and II. Thus, centralizing these functions into a core will not only improve efficiency but also will foster the uniformity that is essential to compare language growth in children with brain injury to growth in children who have not suffered brain injury. Stephen Raudenbush, a leading expert on modeling cognitive growth, will direct the Core, with Susan Goldin-Meadow, Susan Levine, and Steven Small serving as Senior Investigators. RELEVANCE (See instructions): Core C provides centralized statistical services for the research projects I, II and III. The program project is designed to explore the impact of environmental and biological variation on how children learn to use their language for higher order thinking, a key cognitive underpinning of academic and 21st century career success